Remove unnecessary import
Update Django requirement in requirements
Issue 44. Nix fabric requirement for testing

* nix fabfile.py andFabric requirement
* adds run_tests.py for setting up and running the tests
* adds a section to the README on running the tests
Add option to always include a timestamp in build_ids.
Merge pull request #51 from oremj/timestamp_ids

Add option to always include a timestamp in build_ids.
Fix argument defaults for css and js

Argument defaults get evaluated at module load time. So the
debug argument would get the value of whatever
settings.TEMPLATE_DEBUG was at the time the module was loaded.
This is problematic in tests when that setting gets changed
and causes jingo-minify to minify the wrong thing.
Merge pull request #53 from willkg/fix-argument-defaults

Fix argument defaults for css and js
Move utility functions to utils

Moving these three utility functions to their own module makes it easier
to import them without creating a Jinja2 environment as triggered by
registering helpers
Merge pull request #54 from willkg/move-utils

Move utility functions to utils